Zero printing control mechanism



Oct. 7, 1941. I j H. K. F. EWALD' I 2,258,091

ZERO PRINTING CONTROL MECHANISM Original Filed Sept. 3, 1935 Fig.1

Patented Oct. 7, 1941 UNITED PATENT OFFICE 2,258,091 I ZERO PRINTING CONTROL MECHA'NISM iHeinrich Konrad-Friedrich Ewald, Chernnitz,

, ermany, assi nor-to Wand e eWe ke k ie g esellsch aft, .Siegmar-Schiinafl, Germany September 'l, .193;

This invention relates to improvements in printingcalculating machines and particularly to mechanisms thereinfor the'interruption ofautomatic zero printing, including pawls automatical- -ly operated by stops and disposed on thepaper I carriage.

The primary object of the invention 'is to -provide a compact mechanism for this purpose that will be reliable in operation.

According to the present invention the parts operated by the stops on the paper-carriagesare kept retracted, during the travel of the paper carriage, out of the rangeofaction -.ofrthe;stops, and are released for ,cQ-Operation with thelstops at a suitable time during amach-ine operation.

A constructional:example of the mechanism according to the invention. is illustrated .i-n-the accompanying drawing in which; I

Figure 1 is an elevationshowing the printing m hani m Of a calcul t ng machine equipp with the invention; v I ,1.

Fig. 3 is a plan View ofa jp ar.t;of 11511611311181 carriage, and g g The printing mechanism illustrated comprises the usual type carriers I connected to gthe rack sectors 2 of the calculating machine, which rack sectors have bent portions} at'the supper ends. The platen roller 4 is mounted in -the.paper;;car.-.- riage 5 which is slidablein guides 45 on'themachine frame 6a. Duringlprinting the hammers 1 under the action of springs 8 impelwtheetmae carriers l against the platen 4. The-printing hammers l are held inposition of 'resthy lpckir-rg pawls 9 which are acted .upon by springs-l0. The locking pawls 9 are in the .form of two armed levers and have pivoted at .theirfree ends hook members H acted uponbysprings IZ-which tend to hold them below lugs l3-of the locking 'pawls 9. The arrangement is such that the-hook member H of each pawl 9' lies underthelug 13 of the adjacent pawl 9 assigned to thefnextlower-ore dinal place,'Fig. 2.

To return 'the hammers TI to .initial position after printing there is provideda yoke 14 which is actuated by a push rod L5 in the; course .of a machine operation. The push rod] 5 has a-iorked end guided by a pin 15 providedon a disk 1]. The disk I1 is fixed on ashaftwlB connectedby links 36, 31, 38 to the main operating -shait- 39:of, themachineand the disk I] performs atoand fro rocking movement during each oscillationof the main shaft 39. The shaft lfi has asecohd disk [:9 ifixedithereto, Fig. 2. The disks :l1 and 139 are connected to :each other by means of a round bar 10 .on which hammer :releasing pawls 2 l are-.pivotally mounted, which pawls V are .under theiazction of the tension springs 22. The .free ends 'ofthe tension springs are. attached to a rod 2:3. which ;is attached between the disks '1'] and :l;.8. Thelower-ends .ofxthe release pawls 2! ex..- tendfbelowithelugs Q3 .of the rack sectors -12 and are held'byi theglatter normally outiof engagement with the lugs l3 of thelockingpaw-ls-S. 1Whena digitis s t: up -.i.n'one ordinal; place on. the calculatns machine, thelug 3..of;th.e corresponding rack sector fr s the releasepawl 2| assignedto this ordinal place whereby the: lattermoves under the lu "13 of the lockin p wl .9, under theaction f its spring 22- niccm fl-isfixed between th disks 1 and 19, be w en the teeth'oiwhich ar uided push rods 12. w ich are jo n ed-to el cranks .25 an cooperate with the -=fr.ee ends of ,the;re1ease,-Paw1s -l.l The-bell cranks 26 are pivot d a IQdZ'I, c h chia eifixed wo cra ks 28 which toge he wi h an z e end nabetween them, o m a yoke wh ch ser es f r t s multa ou operati n e aa i e -P ds'25, l y' cck ns all the bell cranks 16. This r k g movement of theyoke 28,. 29 is effected ;;by a crank 30 which cooperates with a cam d k 3 the a er e n onne ted. iSShewnin'Eigur-e 1.. by means of ailink sum the main shaft 39 oi: the-machine, .Qpposite the free ends of the bell cranks 2.6 there i ange a ep3? ex haneeablr mountedone bar .33. T is be is nse t d ma i ned slots of a fr m -3 -d sp sed n a su ta le openin of e ba e P at th pasr. a na e 25 and attached by screws 35. .A stop 32, @S'zShOWIl in Figure 4, has three downwardly extending projections.

The operation of -the above :described-P-Iinting mechanismisas follows: 7

A At the-beginning of a machine operation the parts of the printing mechanism lie ine. position differing from-that shown in Figure 1 int-hat the parts connected throughlinks 136, 31, .38 and-A0 to .the main shaft 3.9.-of. the machine occupy; position somewhat displaced in counter-clockwise direction to ithat'illustrated, the cam disk 3l b eing in such a position that the pin of thecranka30 lies on, the part of the camwhichisof-maximum diameter. fT'hegrising' of the .pin .of .the crank.30 causes the yoke.28,; 29 to be forced against the lowerarms of the hell cranks 26,-and the upper arms 0f 'the bell cranks 26 are retracted from the range-of action of t-hestop 32. The pushrods During a machine operation the links 36, 31,

38, 49 are drawn to the left in the forward stroke of the main shaft 39. This brings the "cam disk 3| into the position shown in Figural, and while] the pin of the link 3!! slides on thesmallerdiameter portion of the cam disk 3|, the bell cranks 26 are released to cooperate with the stop 32.

of the range of action on the stop 32. Meanwhile the shaft l8 and the parts fixed thereto have returned to their initial position in which operation the pin I6 of the disk I! forces back the push rod l5 whereby the printinghammers 1 are returned by the yoke l4 into their position of rest.

By use of stops 32 having extensions provided at different places it is possible to interrupt automatic printing at any desired places.

In the mechanism according to the invention the contact ends of the bell cranks 26 are arranged in a plane lying in the direction of the paper carriage'movement. This makes it pos- The upper arms of the bellcranks 26 thusmay contact with the stop 32 andfunless they, en-

counter a downwardly extending projection of the stop 32, they arrive at the position shown in Figure 1. encounter extensions on. the stop 32 are prevented from further upward movement, and their push rods 25 hold the associate release pawls out of engagement with the lugs 13 of the pawls 9. As a result, at those places in the printing mechanism at which there are downwardly projecting extensions on the stop 32, there is an interruption of Zero printing, since the movement of the pawls 9 which release the printing hammers 1 is interrupted by the retraction of the corresponding release pawls At the same time the shaft I8 performs a rotary movement in clockwise direction whereby the round bar 29 between the disks I1 and I9, and the hook members 2| thereon will swing upwardly. Since the pawls 2| have their lower ends extending below the lugs 3 of therack sectors 2 only those hook members 2| engage behind the lugs l3 of the pawls 9, which have been released by the lugs 3, of rack sectors that'have been swung upwardly corresponding to digital values of operated keys. If for example in a calculating machine with ten ordinal places, a digit-has been set up in the sixth place, the sixth rack sector 2 will move up and release the sixth hook memsixth pawl 9 is moved out of its locking position whereby also the sixth printing hammer 1 is released. The release pawl ll of the sixth locking pawl 9 carries with it the fifth pawl 9 and hereby releases the fifth printing hammer I. The release pawl of the fifth locking pawl 9 in turn carries with it the fourthpawl 9, and so on. Thereby all the printing hammers of the lower ordinal places are released.

By means of the stop 32, as above explained, one release pawl may be made inoperative at any desired place, so that from this place downwardly the further operation of the pawls}! is prevented. For example if in a ten ordinal place calculating machine the release pawl between the fifth and fourth place is made inoperative, then in the printing operation, if a digit has been set up in the sixth place, only the printing hammer for the sixth place and that 'for the fift place will be released.

After printing is completed the links 36, 31, 38, 49 are restored to the right during the return stroke of the machine shaft 39. In this movement the crank 30* slides againon the largest diameter part of the cam disk 3| and. by means of the yoke 28, 29 rocks the bell cranks 26 out However, those bell cranks 26 which sible to make thestop 32 for controlling zero printing in the form of a thin plate the dimen- ,sions of-which in the direction of the paper carria'ge movement can be kept comparatively small. By arranging the bell cranks 26 as close as possible to each other, that is with a smaller pitch than that of the members of the printing mechanism, a more compact arrangement is obtained. This is possible because the bell cranks 26 cooperate with the carrier pawls not directly but through push rods 25. The invention thus has the advantage that the parts for controlling the automatic zero printing on the paper carriage are exceptionally compact without affecting the reliability of operation.

The present application is a division of my co-pending application Serial No. 39,065, file September 3, 1935. I

I claim as my invention:

1. In a bookkeeping or calculating machine the combination of a machine frame, a paper carriage slidably arranged on the machine frame, a main drive shaft, a plurality of type-carriers, a plurality of printing-hammers for engaging the type-carriers, a plurality of springs for actuating the printing-hammers, a plurality of locking members for holding the printing-hammers in their position of rest against the action of-the springs, a plurality of controllable means for releasing the printing-hammers each releasing means being controlled in dependence upon the position of its corresponding type-carrier, intermediate members actuated by the main drive shaft for actuating the releasing means, a plurality of coupling members each coupling member being .pivotally connected to a locking memberand coupling the same to the adjacent locking member for effecting automatic zero printing, a plurality of additional springs each of which forces one of the coupling members to its .coupling position, a plurality of settable members each settable member controlling one ,of the coupling members for interrupting automatic zero printing against the action of the corresponding second-named spring, a device for setting simultaneously all the settable members to their. position of interrupting zero printing, a member ar-' ranged on the paper carriage and having at least one projecting portion for retaining at least one settable member in its position of interrupting g zeroprinting, a cam-like device actuated by the main drive shaft for moving the saidsetting device in'such a manner that during the forward strokeof the cam-like device during a printing cycle certain of the settable members are re- I leased 'to their automatic zero printing position under control of the projecting portions of the said member and during the return stroke of the cam-like device after the printing cycle the settable members are again set to their zero printing interrupting position. I

2. In a bookkeeping or calculating machine the combination of a machine frame, a paper carriage slidably arranged on the machine frame, a main drive shaft, a plurality of type-carriers, a plurality of printing-hammers for engaging the type-carriers, a plurality of springs for actuating the printing-hammers, a plurality of locking members for holding the printing-hammers in their position of rest against the action of the springs, a plurality of controllable releasing means for releasing the printing-hammers each releasing means being controlled in dependence upon the position of its corresponding type-carrier, intermediate members actuated by the main drive shaft for actuating the releasing means, a plurality of hooks each hook being pivotally connected to a locking member and coupling the same to the adjacent locking member for effecting automatic zero printing, a plurality of additional springs each of which forces one of the hooks to its coupling position, a plurality of rods each rod controlling one of the hooks for interrupting automatic zero printing against the action of the corresponding second-named spring, a plurality of double-armed levers rotatably arranged in the machine frame each of them being connected with one of the rods, a device for setting simultaneously all the double-arm-ed levers to a position in which the rods are in their zero printing interrupting position, a member arranged on the paper carriage and having at least one projecting portion for retaining at least one double-armed lever in a position in which its corresponding rod is in the zero printing interrupting position, a cam-like device actuated by the main drive shaft for moving the said setting device in such a manner that during the forward stroke of the cam-like device during a printing cycle certain of the rods are released to their automatic zero printing position under control of the projecting portions of the said member and during the return stroke of the cam-like device after the printing cycle the rods are again set to their zero printing interrupting position.

3. In a bookkeeping or calculating machine the combination of a machine frame, a paper carriage slidably arranged on the machine frame, a main drive shaft, a plurality of type-carriers, a plurality of printing-hammers for engaging the typecarriers, a plurality of springs for actuating the printing-hammers, a plurality of pawls for holding the printing-hammers in their position of rest against the action of the springs, a plurality of controllable means for releasing the printinghammers each releasing means being controlled in dependence upon the position of its corresponding type-carrier, intermediate members actuated by the main drive shaft for actuating the releasing means, a plurality of hooks each hook being pivotally connected to a pawl and coupling the same to the adjacent pawl for effecting automatic zero printing, a plurality of additional springs each of which forces one of the hooks to its coupling position, a plurality of rods each rod controlling one of the hooks for interrupting automatic zero printing against the action of the corresponding second-named spring, a shaft arranged in the machine frame,

a plurality of double-armed levers rotatably mounted on the shaft, each of the doublearmed levers being connected with one of the rods, a device for setting simultaneously all the double-armed levers to a position in which the rods are in their zero printing interrupting position, a member arranged on the paper carriage and having at least one projecting portion for retaining at least one double-armed lever in a position in which its corresponding rod is in the zero printing interrupting position, a camlike device actuated by the main drive shaft for moving the said setting device in such a manner that during the forward stroke of the cam-like device during a printing cycle certain of the rods are released to their automatic zero printing position under control of the projecting portions of the said member and during the return stroke of the cam-like device after the printing cycle the rods are again set to their zero printing interrupting position.

4. In a calculating or bookkeeping machine the combination of a machine frame, a paper carriage slidably arranged on the machine frame, a main drive shaft, a plurality of type-carriers, a plurality of printing-hammers for engaging the type-carriers, a plurality of springs for actuating the printing-hammers, a plurality of pawls for holding the printing-hammers in their position of rest against the action of the springs, a plurality of controllable latches each of them being adapted to act upon one of the pawls for releasing one of the printing-hammers each latch being controlled in dependence upon the position of its corresponding type-carrier, intermediate members actuated by the main drive shaft for actuating the latches, a plurality of hooks each hook being pivotally connected to a pawl and coupling the same to the adjacent pawl for effecting automatic zero printing, a plurality of additional springs each of which forces one of the hooks to its coupling position, a plurality of rods each rod controlling one of the hooks for interrupting automatic zero printing against the action of the corresponding second-named spring, a shaft arranged in the machine frame, a plurality of double-armed levers rotatably mounted on the shaft, each of the double-armed levers being connected with one of the rods, a yoke rotatably arranged on the shaft for setting simultaneously all the double-armed levers to a position in which the rods are in their zero printing interrupting position, a member arranged on the paper carriage and having at least one projecting portion for retaining at least one double-armed lever in a position in which its corresponding rod is in the zero printing interrupting position, a camdisk actuated by the main drive shaft for moving the yoke in such a manner that during the forward stroke of the cam-like device during a printing cycle certain of the rods are released to their automatic zero printing position under control of the projecting portions of the said member and during the return stroke of the cam-like device after the printing cycle the rods are again set to their zero printing interrupting position.

HEINRICH KONRAD FRIEDRICH EWALD. 

